HomeMy WebLinkAboutPR 2.7.4; ELLERY RESERVOIR PROPERTY; SOIL INVESTIGATION; 1969-11-12I
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SOIL INVESTIGATION FOR THE PROPOSED
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CITY OF CARLSBAD - WATER SYSTEM' IMPROVEMENTS .'. .
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CARLSBAD,. CALIFORNIA
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ENGINEERING -SCIENCE, INCORPORATED' . ,. .
' ' • ' • 3260-1/2 Rosecrans Avenue • •
San Diego, California
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V RECEIVED, 1 3 1969
I Consulting
WOODWARDCLYDE& ASSOCIATES • : •. •
Soil and Foundation Engineers and Geologists
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TABLE OF CONTENTS . .
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. LETTER OF TRANSMITTAL .
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SCOPE AND DESCRIPTION OF PROJECT
1 . . FIELD INVESTIGATION . . .
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'. LABORATORY TESTS .
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SITE AND SOIL CONDITIONS 4
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S Tank Sites
. . The Mesa Site
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The Elm Site
. . . . The Ellery Site 5
1.. The Skyline Site .. . . 5
Proposed Pipe Lines . . . . . 5
I . DISCUSSION . 5.. . . . 7
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.: CONCLUSIONS AND RECOMMENDATIONS . . 8
Tank Sites' . 8
General: 5 8
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. Mesa -Site .
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Elm, Ellery and Skyline Sites S.
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. Pipe Lines .
S .. 14 . . LIMITATIONS :
I FIGURE 1 - SITE PLAN
FIGURE .2- LOG OF TEST BORING. 1 TANK SITES . . .. . .
I FIGURE 3 - LOGS OF TEST BORINGS 2 & 3 TANK SITES . S
FIGURE 4- LOGS OF TEST BORINGS 4 & 5 TANK SITES . . .
I . FIGURE 5 - LOG OF TEST BORING 6 TANK SITES
I . FIGURE 6 - LOGS OF TEST BORINGS 1 THROUGH 3 PIPE LINES
FIGURE 7:- LOGS OF TEST BORINGS 4 THROUGH 6 PIPE LINES
I FIGURE 8 - LOGS OF TEST BORINGS 7 •THROUGH 9 PIPE LINES .
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FIGURE 9--' LOGS OF TEST BORINGS 10 THROUGH 12 PIPE LINES. S S
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1 TABLE OF CONTENTS (Continued)
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FIGURE 10 - GRAIN SIZE DISTRIBUTION CURVES .
FIGURE 11 -. GRAIN SIZE DISTRIBUTION.CURVES :.
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.. FIGURE 12 - FILL SUITABILITY TESTS
FIGURE 13 - RESULTS OF LOADED SWELL TESTS .
I FIGURE
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14 - RESULTS OF CONFINED COMPRESSION TESTS
I ATTACHMENT I - SPECIFICATIONS FOR CONTROLLED FILL
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i WOOD WARD CLYDE & ASSOCIATES
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CONSULTING SOIL AND FOUNDATION ENGINES AND GEOLOGISTS •.
3467 Kurtz Street November 12, 1969San Diego -
California 92110 Project No. 69-263 •.
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(714) 224-2911 . . . .
I Engineering Science Incorporated . . . . . . . . . .. .
3260-1/2 Rosecrans Avenue
San Diego, California
Attention: Mr. Richard R. Duessen ' ' .. •'
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I In accordance with your request, our proposal dated June 25,"196.19—,
. . ' and your letter of authorization dated July 24, 1969, we, have made
an 'investigation of the uderlying soil conditions at the site, of
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: the proposed City of .Carlsbad- Water System Improvements, your.-
Job No. 782. . • • ' . ,' ' •
The accompanying report'-presents 'our conclusions and recommendations, •
as well as the results of' the 'subsurface exploration and laboratory '
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tests upon which these recommendations are based.
The Engineer assigned to this project was Mr. Richard P. While -of' • '
our firm..
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.. SCOPE PND DESCRIPTION OF PROJECT
This report describes an investigation of the underlying
soil conditions along portions of the proposed new water lines and
I at 4 new water tank sites. Three of the tank sites will be constructed
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. within the limits of the City of Carlsbad and one site will be located
at. the.. site of an existing reservoir' in Oceanside, California.. All.
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'.of:-.the water lines are located in easements in the City of Carlsbad. . .
The study is intended to determine the most suitable type and depth
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of.foundation and the allowable soil bearing pressures to be used in
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design of the tanks, as well as to estimate the magnitude of possible
. , . settlement. In addition the soil conditions along portions of the
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new lines were determined in order to provide a basis for..conclusions
and recommendations pertainingto construction and design of the pipe.
I lines.
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. The approximate locations of the proposed tanks and pipe
lines are, shown on the Site Plan, Fig. 1. It is our understanding
I that the tanks will vary in size from 40 to:160 ft in diameter and
will be of steel, for the smallest 40 ft diameter tank, and either steel
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or reinforced concrete construction for the others. It is proposed.
to place the tanks on ring footings and provide a reinforced concrete . .
I . slab floor. With the exceptton of Mesa site, where the tank will be
placed on existing grade.,it is planned to grade the sites to provide . .
a.level surface for the tanks. In this regard it is understood that
the first tanks will be placed on the cut portion of the resulting .
pad, but that future adjacent tanks will be founded on the fill portion.
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. 'of . the pad.
IWOODWARD CLYDE & ASSOCIATES
Consulting Soil and Foundation Engineers and Geologists
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Cut and fill slopes having inclianti.ons of 1-1/2 to 1 (1-1/2
units horizontal to 1 vertical) and heights of 25 and 20 ft for-cut -
and fill' slopes, respectively, are planned. At the time of this writ-
ing access for drilling to one of the tank' 'sites, the Ellery Site,
had not been-granted. To facilitate design, therefore, assumptions
made concerning the subsurface soils based on a brief visual inspection.
The recommendations included herein are based on these assumptions.
When permission is available borings will be made and an addendum I
letter issued with modifying recommendations if this should be re-
quired. It is our understanding that the water lines will vary in
' size from 8-to 14 in and will have cover depths of from approximately
3' to 15. ft. The deeper portiOns will be located in areas of proposed
roads and shallow cover' is proposed for low, lying areas.
FIELD 'INVESTIGATION
Six test' borings were made at the three tank site's and 11
shallow borings were made at represntative locations. along the proposed
water mains The drilling was done during the period of October 10
and 28, 1969 with a 6-in, diameter truck mounted power auger under '
the supervision of an engineering geologist Two additional hand auger
borings were made in an area which was inaccessible to heavy equip- :
ment. The borings were made at the approximate locations shown 'on
the Site Plan, Fig. 1. Our field informationwas supplemented by in-
formation on file concerning previous projects in adjacent areas.
' , Field boring logs were prepared by the geologist on ,the
basis of an examination of the samples secured and the excavated
material. The Logs of Test Borings presented on Figs. 2 'through 9,
are based on an inspection of the samples, on the laboratory test ,
WOOD WARD CLYDE & ASSOCIATES
Consulting Soil and Foundation Engineers and Geologists
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results, and on the field boring logs. The vertical position of each
sample is shown on the Logs of Test Borings.
The test borings were located in the-field with the aid of
I a plan entitled "City of -Carlsbad Water System" dated August 8, 1969
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and prepared by Engineering Science, Incorporated. Other small topo-
'Engineé'ring graphic maps of the tank sites furnished us by Science,
Incorporated and.numerous maps available on file were used in our
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study.
LABORATORY TESTS
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The soils encountered were visually cálssified and evaluated
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. with respect to strength, swelling and-compressibility characteristics,
I . dry density and moisture content. The classification was substantiated
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by grain size analyses and the determination of plasticity characteristics
on representative samples of the finer grained soils. Fill suitability
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tests, including compaction tests, direct shear tests, expansibility
characteristics, and grain size analyses were performed on samples of
I the probable fill and near surface soils. The strength of-the soils
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. was evaluated by means of direct shear tests on selected samples, and
by consideration of the density and moisture content of the samples
I. . and the penetration resistance of the sampler. Swelling characteristics
were determined by loaded swell tests on both undisturbed and compacted
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. samples. Compressibility characteristics were.established by confined
compression tests on undisturbed samples and by a. consideration of the
geologic characteristics of the soils.
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• The results of tests on undisturbed samples, except for the
loaded swell tests and the confined compression tests, are shownwith
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Consulting Si and Foundation Engineers and Geologists
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the penetration resistance of the sampler at the corresponding sample
location on the Logs of Test Borings. The: grain size distribution
curves are shown and the plasticity characteristics are indicated
on Figs 10 and 11. The fill suitability tests are reported on Fig. 12.
The results of the loaded swell and confined compression tests are
reported on Figs.: 13 and 14, respectively. :
SITE AND SOIL CONDITIONS
Tank Sites
The subject tank sites are located on elevated ridges north
east of the Cities of Carlsbad and Oceanside, California. The ridges
parallel the coast line and geomorphically constitute remnants.of.
more extensive beach ridges that existed in Pleistocene time. The:
existing elevations of the sites are, approximately, 225, 265, 344
and 245 ft for Mesa, Elm, Ellery and Skyline sites respectively.
(USGS datum). . . . . . .
(a) The Mesa site is situated south and adjacent to a large
covered reservoir. Several existing circular tanks and a
chorination station exist. in the area. of the proposed new
tank. The surface of the site is essentially.fiät andlevel
and void of vegetation. The subsurface soils, as indicated
by the test borings, consists of approximately 2-1/2 ft of.
. loose medium dense porous silty fine sand (topsoil) under-
lain by formational soils to the depth explored, approximately
: 23 ft. These materials are composed of dense sandstone of
Pleistocene age the upper 2 to 3 ft of which is partially
: cemented.
(b) The Elm site is located on the upper western flanks of
a beach ridge remnant. At the site the ground slopes sea-
ward on an approximate 8 to linclination. Thesurface is
. essentially natural and grass and weeds sporadically cover
the site. The formational materials underlying the site
Are similar to the Mesa site, however, the topsoils are
somewhat different. One and half to 2-1/2 ft of silty sand
topsoil is underlain by 0 to 1-1/2 ft of sandy clay and constitutes
WOODWARD CLYDE & ASSOCIATES
Consulting Sail and Foundation Engineers and Ceolo gnu
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the residual soil mantle which is underlain to the depth
explored., approximately' 18 ft by dense competent. silty to
clayey sandstone of formational nature. The topsoil .is
generally porous in the upper 12 in. and the underlying
clay is potentially expansive. The formational sandstone
can be considered suitable select material.
A visual inspection of the Ellery site indicates that
subsurface conditions are probably similar to' those di-s-.
closed at the other sites. The tank or tanksl will be
located. on the top of a beach ridge remnant. ,' The surface.
'slopes away gently on both sides and 'is covered with' died.
grasses. Agrove of Eucalyptus trees ..surrounds the site
which is currently Occupied. by a 70 ft diameter water tank.
The most southerly tank site, the Skyline site, is
situated within.but at the edge of a.cu,ltivated field at
the end of Skyline Drive. The site slopes gently westward
on an approximate 10 to 1 inclination. ' The near, surface
soils generally consist of approxiamtely 1 ft of porous
silty sand topsoil underlain by approximately 1-1 /2 ft of
medium dense silty sand. Beneath this residual mantle'.the
formational soils. consist of silty to clayey sandstone
which, as at the other sites, is a relatively competent
unit. The clayey sandstones are essentially..nonexpansive
jn natural states but become low to moderately expansive
when recompacted.
No' groundwater was encountered in any of the test borings
at the tank sites at'the time of drilling..
Proposed Pipe Lines
New water lines will be installed within the City of Carlsbad
in. a variety of physical environments. In general the area involved'
is bordered on the east and west by the aforementioned beach ridge
remnants and the coast, respectively, and on the north and south by
Buena Vista Lagoon and Agua Hedionda, respectively. The ground slopes
gently westward from the beach ridges to a low coastal cliff and
comprises a seaward sloping terrace of Pleistocene age. At the northern
boundary, the southern side slopes of Buena Vista Lagoon are steep;
while at the' southern boundary, the northern slopes at the sides of
WOOD WARD - CLYDE '& ASSOCIATES
Consulting Soil and Foundation Engineers and Geologists
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Agua Hedionda are generally gentle in inclination. Trenches excavated.
on the terrace surface will in general encounter natural and road
" fill soils composed of silty sands and lean.sandy clays with some
I 'gravels. The fill soils in most cases will be beneath existing or
I proposed pavements and are assumed to possess a degree of compaction.
Clean beach sands and gravels were encountered in a portion of Carlsbad
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Boulevard which extends across the mouth of Agua Hedionda Lagoon.
, Sqme caving was experienced while drilling in this area. At the upper
I.. be • . . elevations of the Beach Ridge partially cemented sandstone will
encountered in the trenches -in some areas and may require heavy equip-
ment for trenching the deeper trench portions.
More adverse soil conditions should be anticipated where
'pipe lines are planned in slough (Lagoon)areas. . In, overall aspect the
lagootial soils are unconsolidated soft and loose clays, silts and
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' sands and.in places contain organic material. Surface vegetation is
generally limited to low creeping type plants which can exist in a
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brackish water environment. Whitish salt stains are evident in many
places and standing water exists in pools in the loest areas..
I • . , ' There are two main areas where the proposed' lines come in
contact with the lagoonal soils. One 12 in'. line will extend in an
easement across the .upper end of. Agua Hedionda. Another 12 in, line
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• will be placed in,the proposed Eucalyptus and Marron Streets along
the south side of Buena Vista Lagoon. A third area, located within
Park Drive south of Marine Drive, is adjacent to Agua Hedionda Lagoon,
however, no soft compressible soils are expected to be encountered.
In general hard sandy clays and road fill materials will be excavated.
WOOD WARD - CLYDE & ASSOCIATES
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Soft silty clay and loose silt wi.th ,organic material will
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. be encountered at least in the northern half of the. line extending
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across upper Agua Hedionda Lagoon. The southern half may uncover
improved conditions. This latter portion is approximately 3 to 5 ft
I higher than the northern third and supports a. hardier growth of
vegetation. A high, brackish groundwater level generally within 0
to 5 ft of the surface. is present. .
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Evidence indicates that the steep valley side slopes at the
southern sides of Buena Vista Lagoon extend also at steep inclinations
beneath the lagoonal deposits. Whether or not these materials are
encountered will depend, therefore, on the proximity of the line to the
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. valley slopes. The lagoonal materials are similar to those in Agua
Hedi.onda and brackish water is very near the surface. The valley
1 . slopes are underlain by stiff residual clays which grad6 to formational
sandstone and siltstone of Eocene age. .
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DISCUSSION . .. . . . . .. . .
Two requirements must be fulfilled by any foundation material.
I First, it. must be .safe against shear failure, which would result in
lateral movement of soil from under the load. Second, the vertical
1 . . movement must not exceed the amount permissible for the particular
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type.of structure..
. Granular soils, such as the dense .sands encountered at the . .
tank sites, have good shear strengths when properly compacted and
0 confined. Settlement on such soils is not excessive if the bearing
I capacity is governed by the compactness of the material. Compactness
of natural granular soils is best measured by. the resistance to.
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penetration of the: sampler.. Uniform compactness of granular fill
material can best be secured by engineering supervision of the place-
I ment of the fill.
Factors affecting trenching and pipe laying include; excavat-
ing characteristi.cs of the subsurface soils; presence of.groundwater
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. and -its effecton' construction; and the bearing capacity and slope
stability characteristics of the materials. In general the effects
of these -criteria are' somewhat minimized in dealing with small diameter
pipes placed at shallow depth, such as those planned for the subject
I project. Nevertheless, these criteria should be considered, particularly
tn slough areas where soft soils and high ground Water levels may be
I encountered.
I ' 'CONCLUSIONS AND RECOMMENDATIONS
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The bearing pressures given below were determined on the
'a basis of a minimum safety factor of 3 with. respect to shear failure
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' under the foundation and a negligible differential settlement.
Thjik'Sites
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(I Genera - Based on the results of our subsurface in-
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. vestigation on the Mesa,. Elm and Skyline sites and the assumed similar
'conditions soil at the •Ellery site, it is our opinion that no adverse
I ' soil or geologic conditions exist that-would preclude further develop-
frient. of design for te subject tanks. Some treatment of porous and'
I' potentially expansive surface' soils will be necessary in the tank
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. slab areas during grading. Detailed recommendations are presented
below.
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WOODWARD CLYDE & ASSOCIATES
Conaulting Soli and Foundation EngiQecra and Coologist a
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(2) Mesa Site . ..
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(a) The existing soil conditions at this site in
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.general consist of approximately 2-1/2 ft of loose somewhat porous
silty sand (topsoil) underlain by-3-1/2 ft of dense partially cemented
I ' sandstone which grades downward to uncemented sandstone.
(b) It is recommended that the tank be supported on
spread or ring footings bearing on properly compacted fill or the '
dense sandstone.
(c) It is recommended that the'porous..surface soils
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within the tank area be excavated, properly prepared, replaced.and
properly compacted before footings or slabs are placed.. The tank area,
is defined as the area of the tank plus 5 ft outside these limits. It
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is estimated that the uper 2, ft of soil will have to be recompacted,
however, ,the actual depth of compaction should be controlled in the
I ' field by the soil engineer at the time of grading when the-soils are
exposed.. The replaced soils should be nonexpansive..
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(d). Allowable soil bearing pressures of 2500 psf and '
6000 psf (total load) maybe used on footings extending a minimum
I . . . . depth' of 18 in. below lowest adjacent grade in compacted fill, or
-12in. into sandstone, respectively. I.n the case where proposed grades
may result in compacted fill which is shallow, additional excavation
I and recompaction, should be made so that there is a minimum of 12 in.
of compacted fill below the, bottom of the tank.
It is expected-that settlement will be flegligible
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on interior slabs under soil bearing pressures up to 1500 psf.
(f) ' rn the case of concrete floor slabs it is recommended.
that a 4 in. wetted sand cushion be' provided beneath the slab.
WOODWARD- CLYDE & ASSOCIATES
Constdting Soil and Foundation Engincers and Geologies
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(3) 'Elm, Ell ery. and Skyline'Sites
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(a) It is recommended-that. the footings.for the tanks
at-these sites be founded entirely in natural sandstone. Future
I . . tankloèations proposed for compacted fill areas should be underlain
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. by a minimum depth of 3 ft of compacted fill. '.' . ..
(b) Footings fo.r tank sites located in the cut portion
I of the pad may be designed for an allowable soil bearing pressure of
6000 psf' (total load) at.a minimum depth of 12 in.. below rough grade
in dense sandstone ñiaterals. Footings extending through fill having.
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depths greater than 12 in, should be embeddéd'a minimum depth of -6 in.
tnto sandstone. . . . .. . . . .
1 (c) It is recommended that the interior slabs be.
underlain by a minimum thickness of 12 in. of compacted nonexpansive
I . soil. In order to arrive at this condition, it will be necessary. to
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. undercut and recompact the natural soils in cut areas. In addition
porous topsoils and/or potentially expansive soils may be encountered
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near the daylight boundary during the grading. These soils should be
removed to a depth of 2 ft below rough grade and replaced with properly
compacted nonexpansive soils. . . . . . .
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. (d) It is. recommended that the upper 2 ft of all fill
. . ' be composed of properly compacted nonexpansive soil. The clay soils
I .. may be spread in the, deep parts of the fill. . .
(e) The proposed cut and fill slopes having maximum
1 • heights in the. order of 25 and' 20 ft, respectively, and maximum slope
inclinations of 1-1/2 to 1, will, in our opinion, have adequate factors
of safety against deep seated failure if constructed in accordance with
plans and specifications. . . . .'.
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Consulting Soil and Foundation Engineers and Geologists
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• (f). Concrete slabs-on-grade should be underlain by .
I . . . a minimum 4 in. of clean wetted sand.
(g) In order to minimize differential settlements,
it is recommended that future tank locations be underlain by a minimum
I depth of-3 ft of comapcted fill the upper 2 ft of which should be
S nonexpansive in nature. An allowable:soil bearing of 2500 psf may
I • be depth 18 in.. used on spread or ring footings embedded a minimum of
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. below compacted grade.
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. (4) It is recommended that all earthworking be performed in-
accordance with the attached "Specifications for Controlled Fill" and
• under the supervision of a qualified SoilEngineer. All -compacted S
1 should recommended . fills be tested by the Soil Engineer. It is further
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.that all footing excavations be inspected by Woodward, Clyde and 5
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Associates prior to steel and concrete placement.
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I Pipe Lines.
S ' (5) It is concluded that in general no major adverse soil
I . ' S • conditions will be encountered over most of the proposed new pipe S
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line routes. However, portions of the trenches will encounter uncon- 5
S solidated sediments that may require special consideration. S • •
(6) Natural soil conditions or road fill materials will be
encountered on all of the routes with theexception of those portions .
discussed below.. The natural soils are expected tovary from residual - S
topsoils and clays to moderately, dense sandstone which.in places may
be partially cemented. Road fill materials are expected to be similar
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n classification and should possess adequate strengths to support the
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• (7) No great difficulties with excavation are anticipated
I anywhere along the lines. Some partially cemented sands may be en--
countered in portions of the trenches generally above elevation 200 ft
:(USGS datum). Moderate toheavy excavating but no blasting is anticip-
.: ated in these areas.—
(8). Groundwater is not expected to be encounteredwithin
• the depth expected of excavation except in extreme low land slough
areas. . . 0 ... . •0 .
(9) Unconsolidated sediments consisting of soft clays.and .
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. loose, sands and silts are anticiapted in those areas listed below.
(a) Carlsbad Boulevard between Chinquapin Avenue and
a point approximately 4000 ft south.
.. (b) The 12. in. diameter line crossing the upper end
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of Agua Hedionda Lagoon. This portion is the last
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. section of the line extending from the end of Kelly
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. (c) The 12 in. water line, that wilibeplacedin
proposed Eucalyptus and Marron Streetsalong the south
side of Buena Vista Lagoon. . . .. ... .
Clean beach type sands and gravels are anticiapted .
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.. along Carlsbad Boulevard. In the areas of our borings, and at the
time of drilling, the sands were damp and in our opinion would be
I : relatively stable to depths of 4 or 5-ft. Below this and in areas
were sands are dry, continuous shoring may be -required.
Soft compressible silts and clays will be encountered.
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du,ring trenching that portion described i'(b) above. Somewhat im-
proved conditions are.anticiapted for the south eastern half of this
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portion. Groundwater will be encountered at depths ranging from 0 to
approximately 4 ft and dewatering may be required. . ..
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Consulting Soil and Foundation Engineers and Geologists
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Depending.on the proximity of the water line to the valley
sides,'uncompressible soils similar to those described in paragraph'
Cc) will be encountered in the Buena Vista Lagoon area. To avoid
these soils, it will be necessary.to place the pipe close to the
toe of the natural valley side slopes. Shallow groundwater conditions
may also be encountered in this area. '
Special pipe bedding may•be'required along portions of
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the lines placed in slough areas. Six to 8 in. of crushed rock or
gravel 'should be placed, not only for pipe stability, but to provide
a workable surface during pipe. laying. .
. (.14) Continuous-side shoring or reduced side slopes may be
required in'slough areas particularly below depths o'f.3 ft and where
groundwater levels are near the surface. Side slope inclinations
of 1 to 1 should be stable for short periods of time provided no seepage
pressures exist.
(15) In general the slough clays and silts will have enough
strength to safely support the proposed pipes without dangerous settle-
ment. Some consideration, however, should be given to future plans
for slough areas in regard to placing fills or surcharges after pipes
are laid. Significant pipe settlements could occur over a period of
time particularly in the Upper Agua Hedionda Slough area where,the
pipe may be underlain by thick clay soils. Pipes placed in 'existing
'fills over slough areas may also settle significantly depending on
-thickness of slough deposits and fill soils and time of placement 'of
pipe and fill'.
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Consulting Soil and Foundation Engineers and Geologists
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• V. ••
LIMITATIONS -
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The conclusions and recommendations made in this report are
based on the assumption that the soil conditions do not deviate appreci- I • ably from those disclosed by the test borings or those anticipated by
I • • previous experience in the area of the subject project. Variations
may be encountered and should be anticipated. We should be notified
I . if variations do occur so we may make supplemental recommendations if
this should be required.
. . . . .• . S
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I /
.1
.. S S ••••
S.
I
S •
S
•
55
5 V
•
5
5 .5
I
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I S :...• 55
•
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: 55
5
.
.•
S WOOD WARD -CLYDE & ASSOCIATES
S ..
5 5 ..
5
5
5 Consulting Soil and Foundation Engineers and Geologists
i
• Poring ' - Elm Site
0-
Sk-I F Loose to meditin-dense, dry, light brown
silty fine sand (SM)
Very dense, damp, light brown silty
BC--50 /3 " j fine sand (SM) (Partially cemented
Sandstone)
5- .
8
-
Boring 5 - Skyline Site
- EC 13 Loose, damp to moist, red brown
- silty sand (SM)
t= 10 Medium-dense, moist, red brown silty
t DD=II14 Al sand (SM)
-
C= 50 Dense to very dense, damp, red brown
to gray clayey sand (SC)
C= 71 Very dense, damp, red brown silty,
DS Q' 26 3 sand with lenses of gray clayey
C710 sand (SM-SC)
4-1 CL 10 -
WC= 16 I L'
DD=II7 LJ'
15- EC= 60
Sk6f
WC= 12 /
DO=122 7 Very dense, damp, gray clayey to
20- BC= 77 silty sand (SC-SM) (Moderately
indurated Sandstone)
Very dense, damp, yellow brown silty
C=5013" 8 sand (SM) (Moderately indurated Sandstone)
214- -
[ LOGS OF TEST BORINGS 14 & 5
Note: For Legend, see Fig.. 5; ELM & SKYLINE SITES
I CITY OF CARLS6AD --WATER SYSTEM IMPROVEME!TS
- -- S -- -5 - •S SS - - S -, •SS - .5 5. - 5-., 5-
-:1. ---
--•'
S
.5.- "S
.5
5.' 5 5
5; -.
I
I
I
Boring L
0-
5-
8
+1
t
Cl) -
0 -
CD
8 —
CL
5-
8-
Damp, brown silty sand
}-gravel Fill
Pdium-dense, damp, brown to gray silty
medium to fine sand (S.-SP) (Peach
Sand)
Boring 5• 0
••,
Damp, brown silty medium to fine sand
I • Fill
Medium-dense, damp, gray sandy gravel
(GP) (Peach Gravel)
Medium-dense, damp to moist, light gray
gravelly sand (SP) (Peach Sand)
Boring .6
Very dense, damp, gray sandy gravel
(SP-GP) (Peach sand and gravel) 0
" Note: For Legend, see Fig. 5.
I .
1
Boring 10
Dense, damp, brin clayey sand (Sc)
5-
8-. .
I.. .
S .
S .,. Boringil . . 5-
CD
WC= 32 Soft to firm, moist to saturated,
brown to. gray silty to fine sandWC=y
I
36
ZA clay
1 Lp WC= L2']-- .
Boring 12 .
WC 31 -4f1 Soft to firm, moist to saturated,
I . brn to gray silty to fine sandy
WC= 38 clay (CH-M4) .
qI WC38
Note: For legend, see Fig. 5.
LOGS OF TEST BORINGS 10 THROUGH 12
CITY OF CARLSBAD - WATER SYSTEM' IMPROVEMENTS
- . . . . . JOOE)RD-CLYDE & ASSOCIATES.
.. CONSULTING SOIL ENGINEERS AND.GEOLOGISTS
SAN DIEGO, CALIFORNIA
DR. BY: LCT . ISCALE: =t . . frROJ. O: 69-263
— CK'D BY: DATE: 11-10-69 {FIGURE NO: 9
MECHANICAL ANALYSIS
3 4 1 40 200
DIRECT SHEAR TEST DATA i 2 3
Dry Density, pcf 118 III 116
Initial Water Content, % 9 9 9
Final Water Content. I 13 14 I
Apparent Cohesion. psf 0 0 280
Apparent Friction Angle. ° 32 32 33
111110
WV
80
CD
60
CL
40 C-,
20
0
1000 100 10 1.0 0.1 0.01 0.001
GRAIN SIZE IN MILLIMETERS
0BBLES 'GRAVEL I SAND ISILT & CLA] c j f J m
ACTERISTICS I 2 3
23 Non-
Plastic
28'
13
y Unified Soil
ystem (SM) (SM) (SM)
12 3
sity. pcf -- -- 116
ontent, %
- -- -- 9
-- -- 160
-- -- 5.3
IFIC GRAVITY
AIR VOIDS CURVES
NOTE: Specimen I = Sample 3-2
Specimen 2 = Sample Skt-1
Specimen 3 = Sample Sk 5-6
These samples are taken from borings
drilled at the proposed tank sites.
II 130
120
110
Im
90
80
LABORATORY 'CC1PACTION TEST
LABORATORY COMPACTION ' CITY OF C TEST METHOD: ASTM D I557_64T_
RESULTS OF LOADED SWELL TESTS
Initial Final
Dry
Density
\ter
Content Saturation
Dry
Density
Vbter
Content
*
Saturation
Saiple
Number
Pressure Expansion
pcf. pcf psf % of Initial .Heiit,
2-1 105 25 98 99 32 100 160 5.5
5-2 114 10 60 IILI. ILl. 100 160 0.0
Sk 56 116 9 55 110 18 95 160 5.3
Diai'eter of Saiples: _L93 -in ches
Height of Sarples: approx. .625 inches
s6asi on a specific gravity of 2.65
Note: These samples are taken from borings drilled
at the proposed tank sites.
I
RESULTS OF CONFINED COMPRESSION TESTS
PRESSURE (PSF)
-20M 4000 6000 8000
2
3I
9.-.
c. •• •,
08
10
,final. point aft (r
Jtting
12 . S . •1
Note.: This sample was taken from a boring . .
drilled at the proposed tank site.
• RESULTS OF CONFINED Cc'RESSION TESTS
•
. CITY OF CARLSBAD - WATER SYSTEM IMPROVEMENTS
• WOO4ARD. CLYDE & ASSOCIATES . . .• • CONSULTING SOIL ENGINEERS AND GEOLOGISTS
• . • SAN DIEGO, CALIFORNIA.
. S • . . . • [R. Y: LCT SCALE: frR0J. NO: 69-263
. . • -K'D BY: DATE: 11-10-69 FIGURE NO: 14
I
Initial Final
Conpressidn Number Density Content Saturation Density Content Saturation
Sarple Dry ter * Dry Water * Pressure
pcf. psf %of Initial Height
3-I 97 3 10 110 16 85 6000. 11.7. .
I Attachment
:. : .- .:.. ,:• ..... . ,. .. .; .. . .. '.;,; • .:
I
Project No 69-263
I Page 1 of
I.. '.
SPECIFICATIONS FOR CONTROLLED FILL
I 1 .. .
General - This specification covers preparation of existing
surfaces to receive fills; the type of soil suitable for use in fills;
the control of compaction and the methods of.testing.compacted fills.
I ..
It shall be the Contractor's responsibility to place, spread, water
and compact the fill in strict accordance with these specifications. .
A Soil Engineer shall be the Owner's representative to inspect the .
I ..
construction of fills. Excavation and the placing of fill. shall be.
'. .
under the direct inspection of the Soil Engineer; and, he shall give
written notice of conformance with the specifications upon completion
of grading. Devtatio:n from these specifications will be permitted
only upon Written authorization from the Soil Engineer. A soil in-
vestigation has been made for this project; any recommendations made
in the report shall become an addendum to these specifications. .1
Preparation of Site. - Clear the site of all organic or.o'ther
objectionable material. After being cleared, the existing material"
shall be excavated to the depths and within 'the, limits indicated On
the grading plan. . . . .
I .. '
.
I ..
. . ' ...
The exposed soils in the excavation shall be scarified to a
depth of 6 inches and watered (or allowed to dry) so as to bring them
to a water content that will permit proper compaction. The surface
shall then be compacted with a minimum of .4 passes of a Bros VP-9D or
a vibratory roller having equal or greater weight and rated energy
than the Bros VP-91). The soils shall' then be compacted as hereinafter
' specified for fill. , .. . . .
•
I .'
'Material - Material for use on fill shall be any nonexpansiye
' soil which in the opinion of the Soil Engineer is suitable for use in
constructing fills, and which contains no rocks of six inches or larger
. •'
in diameter', and which contains at least 40 percent of material smaller
than one-quarter inch (1/4") in diameter. For the purpose of this
specification, nonexpa.nsive soils are defined as those soils, which have
a liquid limit less than 30 percent, a plasticity index less than 10
percent and which swell less than three percent when compacted as here-.
inafter specified for compacted fill-while subject to an axial pressure '.
of 150 pounds per square foot in the submerged state.,,'
No materiat of a perishable, spongy, or otherwise improper,
nature shall be used. in the fills.
I . . ' •
' Placing and Compacting Fill Material - The fill material' shall
••'
I •
.be laced in layers which when compacted shall n,ot exceed six inches
'
" (6" in thickness.
' •. After each layer has been placed, mixed and spread evenly,
it shall be-thoroughly compacted to a density not less than ninety
percent (90%) of the maximum laboratory density as determined by .
I
WOODWARD CLYDE & ASSOCIATES
Cnnqulting Soil and Foundation F,ir'in err., and flenlni'ist,
1=
I Attachment I
Project No 69-263
Page 2 of 2
ASTM Test No. D-1557-64T.. Compaction shall be accomplished by vibratory
rollers, multiple-wheel pneumatic-tired rollers, or other types of
acceptable compacting units. Compaction shall be accomplished while
the fill material is at the specified moisture content. Compaction
I . of each layer shall be continuous over its entire area and the com-
pacting equipment shall make sufficient trips over the fill surface
- . to obtain the desired density. ..• .
I ••
. Control of Grading — Control of the fill shall consist of.
• 'field inspection and testing to determine that each layer has been
I '
compacted to the required density at the proper water content. Field
tests shall be made by the Soil Engineer in accordance with 'ASTM Test'
No. D-1557-64T or other methods of obtaining equivalent accuracy.. Density
tests shall be made in the compacted materials below the disturbed fill,
.:I . . .
. surface. When these tests indicate that, the density of any layer or fill
- .. .' • or portion thereof is below the required density, the particular layer '
or portion shall be reworked until the required density has been obtained.
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.•
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WOODWhRD CLYDE & ASSOCIATES 1, - • • • • ' • ...• • • • c, r..:. ..,, ,